Field of the Invention
This application relates to the calibration of laser scanning systems. More particularly, this application relates to a system and method for calibrating a laser scanning system using a motion-controlled camera and a reference calibration plate.
Description of the Related Technology
Laser scanning systems are used in many different applications. One of these applications is the field of additive manufacturing, in which three dimensional solid objects are formed from a digital model. Because the manufactured objects are three dimensional, additive manufacturing is commonly referred to as three dimensional (“3D”) printing. The use of laser scanning systems in additive manufacturing is especially prevalent in stereolithography and selective laser sintering (“SLS”) manufacturing techniques. These techniques use laser scanning systems to direct a laser beam to a specified location in order to polymerize or solidify layers of build materials which are used to create the desired three dimensional (“3D”) object.
The laser scanning systems used in connection with additive manufacturing should provide a very high degree of precision. This high degree of precision helps to ensure that the manufactured object is consistent with the digital model. However, in order to maintain this precision over time, laser scanning systems must be calibrated for various reasons. In some instances, the calibration is necessary due to variations in the laser beam which develop with use of the device. In other instances, temperature fluctuations may impact the accuracy of the laser scanning system.
Existing techniques for calibrating laser scanning systems are both expensive and complex. They often involve expensive, limited-use parts which must be made specifically for the machine to be calibrated. Other techniques call for the use of complex sensor systems which also add both cost and complexity to any calibration process. In view of these and other problems identified by the inventors, a need for fast, accurate, and automated techniques for calibrating laser scanning systems is needed.